Program-clock



(No Model.) 2 Sheets-Sheet 1.. E. F. BURRILL.

v PROGRAM CLOCK.

No. 601,850. Patented Apr. 5,1898.

2 SheetsSheet 2.

(No Model.)

B. P. BURRILL. PROGRAM CLOCK.

No. 6015850. Patented Apr. 5, 1898.

Wi mwow,

UNITED STATES PATENT OFFICE.

ELVYN FREMONT BURRILL, OF OAKLAND, CALIFORNIA.

PROGRAM-CLOCK.

SPECIFICATION forming part of Letters Patent No. 601 ,850, dated April5, 1898.

Applicationfiled September 4, 1896. Serial No. 604,827. (No model.)

To aZZ whom, it may concern:

Beit known that I, ELVYN FREMONT BUR- RILL, a citizen of the UnitedStates, residing at Oakland, county of Alameda, State of California,have invented an Improvement in Program-Clocks; and I hereby declare thefollowing to be a full, clear, and exact description of the same.

My invention relates to that class of devices whereby electric gongs,buzzers, annunciators, relays, or other electrically or mechanicallyoperated devices for signaling or other purposes are set in operation atprescribed times through the agency of a clock. The times at which thesedevices are set in operation refer usually to and indicate some kind ofa program, from which this class of devices has received the generaltitle of pro gram-clocks.

Though my invention is applicable to any kind of a program, for anypurpose, it is especially intended for the exhibition or rendition of aprogram adapted for school purposes.

Myinvention consists in the novel construction, arrangement, andcombination of parts, which I shall hereinafter fully describe andclaim.

Figure 1 is an elevation of my device. Fig. 2 is a top view of theintermediate mechanism. Fig. 3 is avertical section of the clockdial.Fig. 4 is a detail showing the clamping of the hour-wheel sleeve. Fig. 5is a perspective View of the hour-hand with its con tact-lever. Fig. 6is a perspective detail of one of the nodes in position.

I will first describe the parts connected with and immediately dependentupon the operation of the clock.

A represents the dial of an ordinary clock, of which it is unnecessaryherein to illustrate the remaining parts.

B is the ordinary minute-hand of the clock, and O is the hour-hand.

In order to render the hour-hand, which alone is used for the electricalcontacts, true and steady in its movement, there are secured upon asupport D, fastened to the front movement-plate, two strips of thinspring metal (1, mutually clasping the sleeve a of the hourwheel, saidstrips being held together to their frictional contactwith the sleeve bymeans of a binding-screw (1. These metallic strips also serve to conductthe current to the hour-hand, as is shown by the battery-wire w.

The hour-hand O is a heavy, rigid, balanced one, as shown. It isprovided with a strong sleeve 0, having a longitudinal slit in one side,which engages with a pin a, projecting from the outer surface of thesleeve a of the hourwheel. The purpose of this construction is to holdthe hour-hand from turning upon the sleeve of the hour-wheel.

Around the periphery of the dial A and upon its face is secured ametallic circle E, made by bending a strip of sheet springbrass or othersuitable conducting material.

F is a ring cut from bristol-board or other non-conducting material andplaced fiat upon the surface of the dial and close against the base ofthe metallic circle E. This insulatin g-ring may be fitted to the dialeither inside or outside of the metallic circle, but it is here shown asbeing just inside thereof.

G are substantially U shaped metallic nodes or riders movablelongitudinally upon the metallic circle E and frictionally held theretoby the elasticity of their legs or members. Each node is provided with aslender finger g at the lower end of one leg thereof (here shown as theinner leg) and at right angles to it, said finger lying upon the face ofthe insulating-ring F and radial to the dial. The shape of the finger incross-section is that of a right-angled triangle, with one face lyingupon the insulating-ring, another presenting an inclined plane to theapproaching hour-hand, while the third is in a plane perpendicular tothe plane of the dial. There are gutta-percha insulators H for thekeyholes, and also for the center hole of the dial to insulate it fromthe movement and hourhand.

The point of the hour-hand is provided with a downwardly and backwardlybent metallic spring-lever 0, whose tip travels exactly under the pointof the hand and in con stant contact with the face of theinsulatingringF, and consequently trips over the metallic fingers g of the nodes G,which lie across its path.

One circuit-wire w of the light relay-battery V is led to the metalliccircle E as one terminal, and said circuit includes the point IOO of thelever 0 upon the hour-hand as the other terminal, since the othercircuit-wire w is led to the metallic strips, previously described,which conduct the current to the hour-hand. It now follows that whilethe tip of the lever upon the hour-hand is passing across the finger ofa node the electrical circuit will be closed and anyelectrically-actuated apparatus within the circuit will be set inoperation; but for many purposesfor example, ringing gongs in aschool-building to announce the periods of a school-program the durationof this contact would be too long on account of the'slow movement of thehourhand. To reduce the duration of this contact and closure of thecircuit, I have provided the under side of the lever C with a guard 0consisting of a strip of some insulatingor non-conductin g material,which extends from very near the point or extremity of the leverupwardly a sufficient distance, leaving only the very tip of the levereX- posed and so located relatively to the insulating-strip as to comein electrical contact with the node-finger only while crossing the veryupper edge or ridge thereof, for said guard-strip protects it fromcontact while traveling up the slope of the finger, and only whenpassing across the top ridge thereof will the tip of the lever come intoelectrical contact with it.

It will be well at this point in order to make clear the improvedcharacter of the parts thus far described, as well as the utility of theparts to be described, to briefly set forth some difficulties to be metin order to secure the perfect operation of a device of this nature.

It is well known that an apparent mechanical contact of two pieces ofmetal which are terminals of an electric battery is not necessarily anelectrical contact. This is especially true where a metallic pointappears to touch a smooth metallic surface. I have found that it ispossible for a metallic point or terminal to be carried by the movementof a clock-hand across a smooth metallic surface, the other terminal allthe time apparently touching it, without making an electrical contact.If the contact-point on the hand travels constantly upon the surface ofthe insulating-ring between the contactpoints on the dial, as it shoulddo in order to secure the best results, it gathers minute particles ofdust and carries them upon the surfaces of the nodes, and thus impairsthe contact, rendering the action of the current spasmodic or causing itto fail altogether. Devices of this class at present in use employ aflat node with its surface parallel to the plane of the dial, andconsequently fail for the reasons I have ust given.

They are, furthermore, liable to failure for the following reasons: Thenodes controlled by the hour-hand are comparatively broad and the levernaked, thus requiring several minutes for its point to pass across theface of the node. This fact makes it impossible to control the closureof the circuit by means of the hou r-hand alone, so the minute-hand isalso employed, and the closure takes place only when both hands aresimultaneously crossing nodes and continues only so long as theminute-hand lever is in contact with its node. Thus if either thehour-hand or minute-hand contact fails the result is a total failure.

The difficulties I'have described could be overcome if suflicientpressure of the lever upon the node could be secured; but the minute-hand is incapable of imparting more than a very delicate pressure of thelever upon the nodes. Consequently the employment of the minute-hand tocontrol the operation of the closure is an element of weakness andespecially susceptible of failure.

Even employing the minute-hand, as described above, the node must bevery narrow; otherwise the contact is too long; but if it issnfficiently narrow the hand, since it moves in impulses a considerabledistance with each beat of the pendulum, is in danger of jumpin g thenode without making contact.

It will be seen that my device dispenses with the minute-hand and itsnodes as factors in the result at which I aim, thus getting rid of afruitful source of failure. Furthermore, my hour-hand contacts arerendered sure by causing the point of the spring-lever to travel up aninclined plane, thus securing the maximum pressure at the moment ofcontact, and by causing the contact-point to travel across a sharp edgeor ridge of metal, thus securing a scraping of the point, which removesany particles of dust that may be upon it.

Since the parts already described are for many purposes complete, I willshow the manner of setting the nodes for ringing a program, which thedevice is capable of doing perfectly with a singlestroke gong, inasmuchas said gong would strike but once irrespective of the length of thecontact. Suppose, for example, that it is desired to ring a gong or toset any electrically-actuated apparatus in operation by means of theclock at 9 a. m. and again at 2.15 p. m. every day. Turn the hands ofthe clock until they indicate one minute to nine. Then set a node uponthe metallic circle so that its finger lies upon the insulating-ringclose in front of the point of the lever upon the hour-hand. Then bygently sliding it upon the circle so adjust it that the contact-point onthe lever arrives at the edge of the node-finger at exactly nine oclock,which will be indicated by the striking of the gong. Now turn the handsuntil they indicate 2.14 p. m. and set a node in the same manner asbefore. Then set the clock to indicate the correct time of day. It willring the program above indicated every twelve hours as long as the nodesremain in those positions.

Should it be desired to ring the program throughout one portion oftwenty-four hours and not to repeat it during the remaining portion, itis obvious that a switch (unnecessary herein to show) may be so arrangedthat it may, when desired, cut the clock out of the circuit or throw itin again.

Another important advantage in my device may be thus explained. Theduration of the contacts in a model in operation is less than a one-halfminute. It is evident, therefore, that gongs could be rung at any minuteof any hour and at any intervals not less than one minute during aperiod of twelve hours, or on a twenty-four-hour dial during a period oftwenty-four hours. In other devices, since it requires several minutesfor the hour-hand lever to pass across a node, this result could not beobtained. Suppose, for example, it is desired to ring a gong at twelvem., and another at one minute past two p. 1n. It will be necessary,besides the hour-hand nodes, to set a minute-hand node at the figure l2and another at one minute past the figure 12. Now the gong will ring attwelve m., because both hands are simultaneously crossing nodes; but thegong will also ring at one minute past twelve, because the hour-handwill not have passed off the node set for the gong at twelve and theminute-hand will have reached the node set at one minute past twelve.Consequently both hands will again be simultaneously on nodes. Theninstead of there being one gong at one minute past two, as desired,there will also be a gong at two, because the hour-hand in order to beready upon the node set for one minute past two will already have passedupon it when the minutehand crosses the node set for twelve.

As far as I am aware the devices heretofore in use and those suggestedare not intended to operate programs having minutehand nodes nearertogether than five minutes.

Before describing the construction of the intermediate devices which areincluded in my invention and by which, when set in operation by theclock, the program is rendered, I will explain that it is not well toallow the current from a heavybattery to pass through the clock, for thereason that the powerful spark at the moment of breaking contact burnsthe contact-points, even though platinized, and rapidly corrodes them,until the contact is impaired and ruined. There are also corrosivedeposits from local action in the bearings of the movement. So it iscustomary to set a relay between the clock and the main battery. Theclock then closes the circuit of a light relay-battery,which is hereinrepresented by WV, and which actuates the relay. The relay in turncloses the circuit of the main battery, which is here represented by W.

As there are only two contact-points in a relay, the corrosive effectsof the spark can be remedied in a moment by an occasional filling. Nowan ordinary relay is powerless except when under the influence of abattery. \Vhen employed for the purpose above described, such a relayacts so long as the clock maintains its circuit closed and ceases to actthe moment the clock breaks the contact. Now my relay or intermediatedevice diifers in important particulars. I will now describe thisintermediate relay or controlling device.

I represents a suitable frame which carries a power mechanism of anysuitable character, here represented as consisting of spring-actuatedclockwork, (represented generally by J.) Of this clockwork j is theordinary fly or fan regulator, and j is a driven shaft or arbor,conveniently the hour-shaft of an ordinary clock-train. Mounted uponthis shaft or arbor and rotating with it is a cam K, disk-shaped, exceptthat its periphery for a small portion of it falls gently toward thecenter into a depression and then rises again from the deepest part ofthe depression 7c quite abruptly to the circumference. Near this cam andto one side of it is pivoted a lever L, the point of one arm of which isheld by a delicate spring Z against the periphery of the cam K. Thelever L carries fixed to the end of its other arm an armature M of anelectromagnet N, to which the circuit-wires w from the clock and relaybattery extend. The cam-arm of the leverL is provided with a pin L,extending inward to near the face of a small disk 0", rotating on thefan-arbor or outer arbor of the train of gears. The small disk r alsocarries a pin 0", projecting from its face near its periphery outwardtoward the lever L. Now when the point of the lever L rests upon thecircumference of the cam K the pin L is out of the path of the pin 1"and the disk 0 is free to rotate; but when the cam K has made a completerevolution the point of the lever L drops gradually into the depression70 and the pin L begins to interfere with the pin r. When the point ofthe lever rests in the deepest part of the depression 7.", the pin L isexactly in the path of the pin 0' and stops the rotation of the disk 0,which stops the whole mechanism. Since the releasing aud stopping forceis exerted upon a disk and arbor so far removed from the driving power,this construction makes it possible with a delicate releasing force tocontrol apowerfully-driven mechanism. If the stopping were effected byallowing the lever L to fall into a notch in the cam K, to act as adirect pawl, the cam would be driven so forcibly against the pawl thattoo great a force would be required to release it. The circuit from themain battery WV is represented by the wires 10', and this circuitincludes a suitable gong (unnecessary herein to show) or any othermechanism to be ultimately operated to exhibit or render the program.This circuit terminates at one end in a spring-contact 0 against thearbor 7" and at the other end in the post p of a contactspring P,adapted to bear against a contactfinger Q, carried by the cam K. Thiscontactfinger Q, is an adjustable one, being mounted and adapted toslide in a bearing q and being controlled by a spring g, which said IIOspring holds the lower extremity of said contact-finger against an adjListing-cam g 13y turning this cam the contact-finger may be set fartherin or out, in order to increase or diminish the length of time which bythe revolution of the cam K it remains in electrical connection with thecontact-spring P. Now it will be seen that when the light relay-circuitw from the clock is closed by the hourhand, as heretofore described, theelectromagnet N will be energized and will attract its armature M, sothat the lever L will be lifted out of the depression 75 in the cam K;also, the pin L will be lifted out of the path of the pin 1'. The diskr, and consequently the cam K, will now rotate under the operation ofthe power mechanism, and the finger Q and spring P will-be thrown intoelectrical contact and continue therein for any length of time desired,whereby the ultimate device, whether it be the gong-or any othermechanism, will be operated. The cam K will make one rotation, when thelever L will fall into the depression and the mechanism will be stopped,as above described. It will therefore be seen that this controllingdevice is dependent upon the clock only for its release. It is thereforeself-acting, self-timin g, and self-stopping mechanically. As aself-acting relay for ringing a program it is more effective than theminute-hand of the clock in controlling the duration of contact, for bythe rotation of the cam, which may have any suitable diameter, I causethe moving contactiinger Q to travel a long distance at each action andcan cause the electrical contact to be made at any desired point in itsrevolution and continue any desired portion of it from an instantaneousone to one continuing throughout the entire rotation. Thus the durationof contact is put under perfect control; also, since the rotating cam isnear the drivingpower, it yields a strong pressure of the contact-pointsupon each other, securing neverfailing contact.

The closer control of the duration of contact even than is yielded by mydevices on the clock is highly desirable for several purposesforexample, in ringing a school-program with ordinary rapid-striking gongs.In this case the clock alone, or with an ordinary relay, would make toolong a contact. With this intermediate device all that is necessary inthe clock is that the lever pass over the node-finger in a less timethan is required for one rotation of the cam Ksay one minute, which fora school-program apparatus adapted to ring one-minute intervals is aconvenient time. The function of this intermediate apparatus need not beelectrical. It may be mechanical. For instance, it could be used to setoff the heavy striking machinery of a tower-clock, making it possible todetach the striking machinery from the clock, or for other mechanicalpurposes.

In practice, if found desirable, a second metallic circle and relay maybe employed to ring two or more independent programs coujointly.

Having thus described my invention, what I claim as new, and desire tosecure by Letters Patent, is

1. In a program-clock, the combination of a dial having an annularflange or circle, a node consisting of a substantially U-shaped platehaving resilient side arms or members adapted to straddle said flange orcircle and to be adjusted to different points thereon, a fingerprojecting transversely and directly from the lower extremity of one ofthe legs of the node and being of a substantiallyright-angled-triangular shape in cross-section, an electricallyoperatedclock-hand having an underbent lever on its outer end, adapted to extendin the direction of the movement of the hand and to travel up the slopeof the finger and an insulating-strip on the under side of the lever andcovering the major portion and exposing the point thereof whereby thelever travels up the slope and makes contact with the ridge or edge ofthe finger.

2. In a program-clock, the combination of a dial having an annularflange or circle, set on edge, a substantially U-shaped plate or nodehaving its side legs or members to embrace and frictionally engage saidflange or circle, one of said legs having rigid with and projectingdirectly from its lower extremity a contact-finger triangular incross-section, an electrically-connected hour-hand of a clock mechanism,a ring of insulating material litted to the dial at one side of thecircle or flange, and upon which the broad iiat base of the finger lies,an underbent lever carried by the hand and having on its under surfacean insulating-strip which exposesonly the extremity of the lever toelectrical contact with the upper edge or ridge of the contact-finger,and the minute-hand of the clock mechanism independent of the electriccircuit.

3. In a program-clock and in combination with a timepiece, an electriccircuit and connections by which a hand of the timepiece is adapted toclose said circuit at prescribed times, an intermediate device set inoperation by the closing of said circuit and adapted to actuate theultimate mechanism for rendering the program, said device consisting ofa power mechanism, a cam rotated thereby, a lever for releasing andstopping said cam, an electromagnet and armature operated by thetimepiece-circuit to actuate the lever, a fixed electricalcontact-piece, and a contact-finger carried by thecam and adapted tomake and break electrical contact with said piece.

t. In a program-clock and in combination with a timepiece, an electriccircuit and connections by which a hand of the timepiece is adapted toclose said circuit at prescribed times, an intermediate device set inoperation by the closing of said circuit and adapted to actuate theultimate mechanism for rendering the program, said device consisting ofa power mechanism, a cam rotated thereby, a

lever and means controlled thereby and operating through the fly or fanregulating device of the power mechanism for releasing and stopping saidcam, an electromagnet and armature operated by the timepiece-circuit toactuate the lever, a fixed electrical contactpiece, and a contact-fingercarried by the cam and adapted to make and break electrical contact withsaid piece.

5. In a program-clock, and in combination with a timepiece, an electriccircuit and connections by which a hand of the timepiece is adapted toclose said circuit at prescribed times, an intermediate device set inoperation by the closing of said circuit and adapted to actuate theultimate mechanism for render-

